tcp: add tcpi_min_rtt and tcpi_notsent_bytes to tcp_info
tcpi_min_rtt reports the minimal rtt observed by TCP stack for the flow,
in usec unit. Might be ~0U if not yet known.
tcpi_notsent_bytes reports the amount of bytes in the write queue that
were not yet sent.
This is done in a single patch to not add a temporary 32bit padding hole
in tcp_info.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index 014f18e..f93150d 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -2642,6 +2642,7 @@
const struct inet_connection_sock *icsk = inet_csk(sk);
u32 now = tcp_time_stamp;
unsigned int start;
+ int notsent_bytes;
u64 rate64;
u32 rate;
@@ -2722,6 +2723,11 @@
} while (u64_stats_fetch_retry_irq(&tp->syncp, start));
info->tcpi_segs_out = tp->segs_out;
info->tcpi_segs_in = tp->segs_in;
+
+ notsent_bytes = READ_ONCE(tp->write_seq) - READ_ONCE(tp->snd_nxt);
+ info->tcpi_notsent_bytes = max(0, notsent_bytes);
+
+ info->tcpi_min_rtt = tcp_min_rtt(tp);
}
EXPORT_SYMBOL_GPL(tcp_get_info);